U.S. patent application number 09/788261 was filed with the patent office on 2001-11-01 for fuel oils based on middle distillates and copolymers of ethylene and unsaturated carboxylic esters.
Invention is credited to Krull, Matthias, Kupetz, Markus, Nagel, Waltraud, Reimann, Werner, Wildfang, Raimund.
Application Number | 20010034968 09/788261 |
Document ID | / |
Family ID | 26038096 |
Filed Date | 2001-11-01 |
United States Patent
Application |
20010034968 |
Kind Code |
A1 |
Krull, Matthias ; et
al. |
November 1, 2001 |
Fuel oils based on middle distillates and copolymers of ethylene
and unsaturated carboxylic esters
Abstract
A fuel oil comprising: A) a mineral oil having a cloud point of
less than -8.degree. C., a boiling range (90-20%) of less than
120.degree. C. and a difference between CFPP and PP of less than
10.degree. C., and B) one or more copolymers, wherein the
copolymers comprise: a) bivalent structural unit (B1), wherein (B1)
is a bivalent structural unit of formula (1) --CH.sub.2--CH.sub.2--
(1) and b) one or more bivalent structural units (B2), wherein (B2)
is either a bivalent structural unit of formula (2)
--CH.sub.2--CR.sup.1R.sup.2-- (2) in which R.sup.1 is hydrogen or
methyl, R.sup.2 is COOR.sup.3, OR.sup.3 or OCOR.sup.3, and R.sup.3
is an alkyl radical having at least 4 and at most 30 carbon atoms,
or (B2) is a bivalent structural unit of formula (2a) 1 in which
R.sup.3 is an alkyl radical having at least 4 and at most 30 carbon
atoms.
Inventors: |
Krull, Matthias;
(Oberhausen, DE) ; Reimann, Werner; (Frankfurt,
DE) ; Kupetz, Markus; (Dinslaken, DE) ; Nagel,
Waltraud; (Oberhausen, DE) ; Wildfang, Raimund;
(Oberhausen, DE) |
Correspondence
Address: |
CLARIANT CORPORATION
4331 CHESAPEAKE DR
ATTN: INDUSTRIAL PROPERTY DEPT
CHARLOTTE
NC
28216
US
|
Family ID: |
26038096 |
Appl. No.: |
09/788261 |
Filed: |
February 19, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
09788261 |
Feb 19, 2001 |
|
|
|
09111548 |
Jul 7, 1998 |
|
|
|
Current U.S.
Class: |
44/393 |
Current CPC
Class: |
C10L 1/1955 20130101;
C10L 1/1973 20130101; C10L 1/2364 20130101; C10L 1/1963
20130101 |
Class at
Publication: |
44/393 |
International
Class: |
C10L 001/18 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 8, 1997 |
DE |
197 29 055.8 |
Claims
We claim:
1. A fuel oil middle distillate composition comprising: A) a
mineral oil having a cloud point of less than -8.degree. C., a
boiling range (90-20%) of less than 120.degree. C., a 95%
distillation point of less than 350.degree. C. and a difference
between CFPP and PP of less than 10.degree. C., and B) one or more
copolymers present in an amount of 0.001 to 2% by weight, based on
the weight of the oil, wherein the copolymers have melt viscosities
of from 20 to 10,000 mPas at 140.degree. C. and wherein the
copolymers consist essentially of a) and b): a) bivalent structural
unit (B1) present in an amount of from 85 to 97 mol %, wherein (B1)
is a bivalent structural unit of formula (1)--CH.sub.2--CH.sub.2--
(1)and b) one or more bivalent structural units (B2) present in an
amount of from 3 to 15 mol % of, wherein (B2) is either a bivalent
structural unit of formula (2):--CH.sub.2--CR.sup.1R.su- p.2--
(2)in which R.sup.4 is hydrogen or methyl, R.sup.2 is COOR.sup.3,
OR.sup.3 or OCOR.sup.3, and R.sup.3 is an alkyl radical having at
least 4 an at most 30 carbon atoms, or (B2) is a bivalent
structural unit of formula (2a) 8in which R.sup.3 is an alkyl
radical having at least 4 and at most 30 carbon atoms, wherein the
copolymers comprise up to 5% by weight of further comonomers.
2. The fuel oil composition as claimed in claim 1, wherein R.sup.1
is hydrogen.
3. The fuel oil composition as claimed in claim 1, wherein R.sup.3
in the bivalent structural units (B2) is C.sub.5-C.sub.24-alkyl or
a neoalkyl radical having 7 to 11 carbon atoms.
4. The fuel oil composition as claimed in claim 1, wherein R.sup.3
in the bivalent structural units (B2) is C.sub.8-C.sub.18-alkyl or
a neoalkyl radical having 8, 9 or 10 carbon atoms.
5. The fuel oil composition as claimed in claim 1, wherein the
copolymers stated under B) have melt viscosities at 140.degree. C.
of from 30 to 5000 mPas.
6. The fuel oil composition as claimed in claim 5, wherein the
copolymers stated under B) have melt viscosities at 140.degree. C.
of from 50 to 2000 mPas.
7. The fuel oil composition as claimed in claim 1, wherein the
structural units (B1) and (B2) stated under B) are selected from
the group consisting of vinyl ethers, alkylacrylates, alkyl
methacrylates or higher olefins having at least 5 carbon atoms.
8. The fuel oil composition as claimed in claim 7, wherein the
higher olefins are selected from the group consisting of hexene,
4-methylpentene, octene and diisobutylene.
9. The fuel oil composition as claimed in claim 1, wherein the
mineral oils stated under A) have sulfur contents of less than 500
ppm.
10. The fuel oil composition as claimed in claim 9, wherein the
mineral oils stated under A) have sulfur contents of less than 300
ppm.
11. The fuel oil composition as claimed in claim 10, wherein the
mineral oils stated under A) have sulfur contents of less than 100
ppm.
12. The fuel oil composition as claimed in claim 1, wherein the
mineral oil has a cloud point below -15.degree. C.
13. The fuel oil composition as claimed in claim 1, wherein mineral
oil has a boiling range (90-20%) of less than 100.degree. C.
14. The fuel oil composition as claimed in claim 1, wherein mineral
oil has a boiling range (90-20%) of less than 80.degree. C.
15. The fuel oil composition as claimed in claim 1, wherein the
mineral oil has a 95% distillation point of less than 360.degree.
C.
16. The fuel oil composition as claimed in claim 1, wherein the
composition comprises from 85 to 97 mol % of comonomers (B1) and
from 3 to 15 mol % of comonomers (B2).
17. The fuel oil composition as claimed in claim 16, wherein the
composition comprises from 90 to 96 mol % of comonomers (B1) and
from 4 to 10 mol % of comonomers (B2).
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application is a continuation-in-part of U.S.
application Ser. No. 09/111,548, filed on Jul. 7, 1998.
FIELD OF THE INVENTION
[0002] The present invention relates to fuel oils which comprise
middle distillates and copolymers of ethylene and esters of
unsaturated carboxylic acids and which exhibit improved cold flow
behavior.
BACKGROUND OF THE INVENTION
[0003] Crude oils and middle distillates such as gas oil, diesel
oil or heating oil, obtained by distillation of crude oils,
contain, depending on the origin of the crude oils, different
amounts of n-paraffins, which crystallize out as lamellar crystals
when the temperature is lowered and in some cases agglomerate with
inclusion of oil. This results in a deterioration in the flow
properties of these oils or distillates, giving rise to problems,
for example in the recovery, transport, storage and/or use of the
mineral oils and mineral oil distillates. In the case of mineral
oils, this crystallization phenomenon can lead to deposits on the
pipe walls during transport through pipelines, especially in the
winter, and in individual cases, for example when the pipeline is
shut down, even to complete blockage thereof. The precipitation of
paraffins can also cause difficulties in storage and further
processing of the mineral oils. Thus, it may be necessary in winter
to store the mineral oils in heated tanks. In the case of mineral
oil distillates, blockage of the filters in diesel engines and
furnaces may occur owing to the crystallization, with the result
that reliable metering of the fuels is prevented and complete
interruption of the fuel or heating medium feed may occur.
[0004] In addition to the traditional methods for eliminating the
paraffins which have crystallized out (thermally, mechanically or
by means of solvents), which relate only to the removal of the
precipitates already formed, recent years have seen the development
of chemical additives (so-called flow improvers or paraffin
inhibitors) which physically interact with the precipitating
paraffin crystals and thus modify their shape, size and adhesion
properties. The additives act as additional crystal seeds and
partially crystallize out with the paraffins, resulting in a larger
number of smaller paraffin crystals with modified crystal shapes. A
part of the action of the additives is also explained by dispersing
of the paraffin crystals. Modified paraffin crystals have less
tendency to agglomerate, so that the oils into which additives have
been introduced can be pumped or processed even at temperatures
which are often more than 20.degree. lower than in the case of oils
not containing additives.
[0005] The flow and low-temperature behavior of mineral oils and
mineral oil distillates is described by stating the pour point
(determined according to ISO 3016) and the cold filter plugging
point (CFPP; determined according to EN 116). Both characteristics
are measured in .degree.C.
[0006] Typical flow improvers for crude oil and middle oil
distillates are copolymers of ethylene with carboxylic esters of
vinyl alcohol. Thus, according to DE-A-11 47 799, oil-soluble
copolymers of ethylene and vinyl acetate having a molecular weight
between about 1,000 and 3,000 are added to mineral oil distillate
fuels having a boiling point between about 120 and 400.degree. C.
Copolymers which contain from about 60 to 99% by weight of ethylene
and from about 1 to 40% by weight of vinyl acetate are preferred.
They are particularly effective if they were prepared by free
radical polymerization in an inert solvent at temperatures of from
about 70 to 130.degree. C. and pressures of from 35 to 2,100 atm
(gauge pressure) (DE-A-19 14 756).
[0007] Other polymers used as flow improvers contain, in addition
to ethylene and vinyl acetate, for example 1-hexene (cf. EP-A-0 184
083), diisobutylene (cf. EP-A-0 203 554) or an isoolefin of the
formula 2
[0008] in which R and R' are identical or different and are
hydrogen or C.sub.1-C.sub.4-alkyl radicals (EP-A-0 099 646).
Copolymers of ethylene, alkenecarboxylic esters and/or vinyl esters
and vinyl ketone are also used as pour point depressants and for
improving the flow behavior of crude oils and middle distillates of
crude oils (EP-A-0 111 888).
[0009] In addition, copolymers based on .alpha.,.beta.-unsaturated
compounds and maleic anhydride are also used as flow improvers.
DE-196 45 603 describes copolymers of from 60 to 99 mol % of
structural units derived from ethylene and from 1 to 40 mol % of
structural units which are derived from maleic acid, its anhydride
or its imides.
[0010] DE-1 162 630 discloses copolymers of ethylene and vinyl
esters of straight-chain fatty acids having 4 to 18 carbon atoms as
a pour point-depressing additive for distillate fuels having a
medium boiling point, such as heating oil or diesel oil.
[0011] EP-A-0 217 602 discloses ethylene copolymers with vinyl
esters carrying C.sub.1- to C.sub.18-alkyl radicals as flow
improvers for mineral oil distillates having boiling ranges
(90-20%) of less than 100.degree. C.
[0012] EP-A-0 493 769 discloses terpolymers which are prepared from
ethylene, vinyl acetate and vinyl neononanoate or neodecanoate, and
their use as additives for mineral oil distillates.
[0013] EP-A-0 746 598 discloses copolymers of ethylene and dialkyl
fumarates as a mixture with mineral oils which a cloud point of
less than -10.degree. C.
[0014] The efficacy of the known additives for improving the
properties of mineral oil fractions is dependent, inter alia, on
the origin of the mineral oil from which they were obtained and,
hence, in particular on its composition. Additives which are very
suitable for establishing specific properties of fractions of a
crude oil can therefore lead to completely unsatisfactory results
in the case of distillates of crude oils of different origin.
[0015] Against the background of the increased environmental
consciousness, fuels which give rise to less environmental
pollution during their combustion have recently been produced.
Appropriate diesel fuels are distinguished by a very low sulfur
content of less than 500 ppm and in particular less than 100 ppm, a
low aromatics content and a low density of less than 0.86, in
particular less than 0.84, g/ml. They cannot be treated with
conventional flow improvers or can be treated therewith only to an
inadequate extent. In particular, the winter grades of diesel fuels
produced for use under arctic conditions and having extreme
low-temperature properties, such as, for example, a cloud point of
less than -8.degree. C. and in particular less than -15.degree. C.,
very narrow distillation cuts with boiling ranges of 20 to 90% by
volume below 120.degree. C., in particular below 100.degree. C. and
in some cases also below 80.degree. C., and a distillation volume
of 95% by volume at temperatures below 360.degree. C., in
particular below 350.degree. C. and especially below 330.degree.
C., present problems. The low-temperature properties of such
distillates can be satisfactorily improved at present only by
adding low-boiling, low-paraffin components, such as, for example,
kerosene.
[0016] The composition caused by narrow distillation cuts and low
final boiling points presents problems with regard to the response
behavior of flow improvers in these oils. These oils have a
paraffin distribution with a maximum at about C.sub.12 to C.sub.14
and contain only insignificant amounts of the n-paraffins
crystallizing out of conventional grades and having hydrocarbon
chains longer than C.sub.18. The cloud points and CFPP values are
so low, especially in the case of winter grades, that conventional
flow improvers do not respond and the low-temperature properties
must be established by dilution with kerosine.
[0017] It was therefore an object of the present invention to
develop new fuel oils having an improved low-temperature
flowability compared with the prior art.
[0018] Surprisingly, it has been found that main chain polymers of
ethylene which carry side chains having more than 5 carbon atoms
are suitable for lowering the CFPP also in the above described
middle distillates. Ethylene/vinyl acetate copolymers having
corresponding comonomer contents are on the other hand virtually
insoluble in hydrocarbons.
SUMMARY OF THE INVENTION
[0019] The present invention relates to a fuel oil comprising:
[0020] A) a mineral oil having a cloud point of less than
-8.degree. C., a boiling range (90-20%) of less than 120.degree. C.
and a difference between CFPP and PP of less than 10.degree.
C.,
[0021] and
[0022] B) one or more copolymers, wherein the copolymers
comprise:
[0023] a) bivalent structural unit (B1), wherein (B1) is a bivalent
structural unit of formula (1)
--CH.sub.2--CH.sub.2-- (1)
[0024] and
[0025] b) one or more bivalent structural units (B2), wherein (B2)
is either a bivalent structural unit of formula (2)
--CH.sub.2--CR.sup.1R.sup.2-- (2)
[0026] in which
[0027] R.sup.1 is hydrogen or methyl,
[0028] R.sup.2 is COOR.sup.3, OR.sup.3 or OCOR.sup.3, and
[0029] R.sup.3 is an alkyl radical having at least 4 and at most 30
carbon atoms,
[0030] or
[0031] (B2) is a bivalent structural unit of formula (2a) 3
[0032] in which
[0033] R.sup.3 is an alkyl radical having at least 4 and at most 30
carbon atoms.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0034] As stated above, the present invention relates to a fuel oil
comprising:
[0035] A) a mineral oil having a cloud point of less than
-8.degree. C., a boiling range (90-20%) of less than 120.degree. C.
and a difference between CFPP and PP of less than 10.degree.
C.,
[0036] and
[0037] B) one or more copolymers, wherein the copolymers
comprise:
[0038] a) bivalent structural unit (B1), wherein (B1) is a bivalent
structural unit of formula (1)
--CH.sub.2--CH.sub.2-- (1)
[0039] and
[0040] b) one or more bivalent structural units (B2), wherein (B2)
is either a bivalent structural unit of formula (2)
--CH.sub.2--CR.sup.1R.sup.2-- (2)
[0041] in which
[0042] R.sup.1 is hydrogen or methyl,
[0043] R.sup.2 is COOR.sup.3, OR.sup.3 or OCOR.sup.3, and
[0044] R.sup.3 is an alkyl radical having at least 4 and at most 30
carbon atoms,
[0045] or
[0046] (B2) is a bivalent structural unit of formula (2a) 4
[0047] in which
[0048] R.sup.3 is an alkyl radical having at least 4 and at most 30
carbon atoms.
[0049] As for B2), R.sup.1 is preferably hydrogen. R.sup.3 is
preferably a linear or branched C.sub.5-C.sub.24-alkyl radical,
particularly preferably a linear or branched C.sub.8-C.sub.18-alkyl
radical. In a further, particularly preferred embodiment of the
present invention, R.sup.3 is a neoalkyl radical having 7 to 11
carbon atoms, in particular a neoalkyl radical having 8, 9 or 10
carbon atoms. The neoalkanoic acids from which the abovementioned
neoalkyl radicals can be derived are described by the formula (3):
5
[0050] R' and R" are linear alkyl radicals having together
preferably 5 to 9, in particular 6, 7 or 8, carbon atoms. The vinyl
ester used for the copolymerization accordingly has the formula
(4): 6
[0051] wherein R' and R" are defined as in formula (3).
[0052] Further suitable comonomers are those which can be derived
from acrylic acid: 7
[0053] wherein R.sup.3 is an alkyl radical having at least 4 and at
most 30 carbon atoms. Preferred radicals R.sup.3 are, for example,
butyl, tert-butyl, pentyl, neopentyl, octyl, 2-ethylhexyl, decyl,
dodecyl, tetradecyl, hexadecyl, octadecyl and behenyl.
[0054] The sulfur content of the mineral oils stated under A) is
preferably less than 500, particularly less than 300, ppm,
especially less than 100 ppm. Their cloud point is preferably less
than -15.degree. C. The boiling ranges (90-20%) of the distillation
cuts are preferably less than 100.degree. C., in particular less
than 80.degree. C. The use of mineral oils having a 95%
distillation point of less than 360.degree. C., in particular less
than 350.degree. C., especially less than 330.degree. C., is
preferred.
[0055] The fuel oil compositions according to the present invention
preferably comprise copolymers in which the comonomers (B1) are
present in an amount of from 85 to 97 mol % and the comonomers (B2)
are present in an amount of from 3 to 15 mol %. From 4 to 10 mol %
of (B2) and from 90 to 96 mol % of (B1) are particularly preferred.
The copolymers stated under B) can be prepared by the conventional
copolymerization methods, such as, for example, suspension
polymerization, solution polymerization, gas-phase polymerization
or high-pressure mass polymerization. The high-pressure mass
polymerization at pressures of, preferably, from 50 to 400, in
particular from 100 to 300, MPa and temperatures of, preferably,
from 50 to 300.degree. C., in particular from 100 to 250.degree.
C., is preferred. The reaction of the monomers is initiated by
initiators forming free radicals (free radical chain initiators).
This class of substances includes, for example, oxygen,
hydroperoxides, peroxides and azo compounds, such as cumyl
hydroperoxide, tert-butyl hydroperoxide, dilauroyl peroxide,
dibenzoyl peroxide, bis(2-ethylhexyl)peroxocarbonate, tert-butyl
perpivalate, tert-butyl permaleate, tert-butyl perbenzoate, dicumyl
peroxide, tert-butyl cumyl peroxide, di-(tert-butyl) peroxide,
2,2'-azobis(2-methylpropanonitrile) and
2,2'-azobis(2-methylbutyronitrile- ). The initiators are used
individually or as a mixture comprising two or more substances in
amounts of from 0.001 to 20% by weight, preferably from 0.01 to 10%
by weight, based on the monomer mixture.
[0056] Preferably, the copolymers stated under B) have melt
viscosities at 140.degree. C. of from 20 to 10,000 mPas, in
particular from 30 to 5000 mPas, especially from 50 to 2000 mPas.
The desired melt viscosity of these copolymers is established for a
given composition of the monomer mixture by varying the reaction
parameters pressure and temperature and, if required, by adding
moderators. Hydrogen, saturated or unsaturated hydrocarbon, e.g.
propane, aldehydes, e.g. propionaldehyde, n-butyraldehyde or
isobutyraldehyde, ketones, e.g. acetone, methyl ethyl ketone,
methyl isobutyl ketone or cyclohexanone, or alcohols, e.g. butanol,
have proven useful as moderators. Depending on the intended
viscosity, the moderators are used in amounts of up to 20% by
weight, preferably from 0.05 to 10% by weight, based on the monomer
mixture.
[0057] The copolymers stated under B) may optionally comprise up to
4% by weight of vinyl acetate. The copolymers stated under B) may
optionally comprise up to 5% by weight of further comonomers
wherein further comonomers include copolymers except vinyl acetate
(i.e. since vinyl acetate may only be present up to 4% by weight).
Such further comonomers include, but are not limited to, vinyl
esters, vinyl ethers, alkyl acrylates, alkyl methacrylates or
higher olefins having at least 5 carbon atoms. Preferred higher
olefins are hexene, 4-methylpentene, octene or diisobutylene.
[0058] In order to obtain the copolymers stated under B), monomer
mixtures which comprise, in addition to ethylene and, if required,
a moderator, from 1 to 50% by weight, preferably from 3 to 40% by
weight, of comonomers are used. The different polymerization rates
of the monomers are taken into account by virtue of the fact that
the composition of the monomer mixture differs from the composition
of the copolymer. The polymers are obtained as colorless melts
which solidify to waxy solids at room temperature.
[0059] The high-pressure mass polymerization is carried out
batchwise or continuously in known high-pressure reactors, for
example, autoclaves or tube reactors; tube reactors have proven
particularly useful. Solvents, such as aliphatic and/or aromatic
hydrocarbons or hydrocarbon mixtures, benzene or toluene, may be
contained in the reaction mixture. The solvent-free procedure is
preferred. In a preferred embodiment of the polymerization, the
mixture comprising the monomers, the initiator and, if used, the
moderator is fed to a tube reactor via the reactor inlet and via
one or more side branches. The monomer streams may have different
compositions here (EP-A-0 271 738).
[0060] The copolymers stated under B) are added to the mineral oils
or mineral oil distillates stated under A) in the form of solutions
or dispersions. These solutions or dispersions comprise preferably
from 1 to 90, in particular from 10 to 80, % by weight of the
copolymers. Suitable solvents or dispersants are aliphatic and/or
aromatic hydrocarbons or hydrocarbon mixtures, for example gasoline
fractions, kerosine, decane, pentadecane, toluene, xylene,
ethylbenzene or commercial solvent mixtures, such as Solvent
Naphtha, SHELLSOL.RTM. AB, SOLVESSO.RTM. 150, SOLVESSO.RTM. 200,
EXXSOL.RTM., ISOPAR.RTM. and SHELLSOL.RTM. D types. The fuel oils
according to the present invention comprise preferably from 0.001
to 2, in particular from 0.005 to 0.5, % by weight of copolymer,
based on the distillate.
[0061] The compound of the formula (2a) is a copolymerized maleic
imide, the imide itself having a double bond between the --CH--CH--
groups. The compound of the formula (2a) can either be produced by
copolymerizing a maleic imide, or by copolymerizing maleic
acid/maleic anhydride and subsequent imidization of the copolymer
with an amine.
[0062] The fuel oils according to the present invention may
comprise further oil-soluble coadditives which by themselves
improve the cold flow properties of crude oils, lubricating oils or
fuel oils. Examples of such coadditives are vinyl
acetate-containing copolymers or terpolymers of ethylene, polar
compounds which disperse paraffins (paraffin dispersants) and
comb-like polymers.
[0063] Oil-soluble polar compounds having ionic or polar groups,
for example, amine salts and/or amides, which are obtained by
reacting aliphatic or aromatic amines, preferably long-chain
aliphatic amines, with aliphatic or aromatic mono-, di-, tri- or
tetracarboxylic acids or anhydrides thereof have proven useful as
paraffin dispersants (cf. U.S. Pat. No. 4,211,534). Other paraffin
dispersants are copolymers of maleic anhydride and
.alpha.,.beta.-unsaturated compounds, which, if required, can be
reacted with primary monoalkylamines and/or aliphatic alcohols (cf.
EP-A-0 154 177), the reaction products of alkenylspirobislactones
with amines (cf. EP-A-0 413 279) and, according to EP-A-0 606 055,
reaction products of terpolymers based on
.alpha.,.beta.-unsaturated dicarboxylic anhydrides,
.alpha.,.beta.-unsaturated compounds and polyoxyalkenyl ethers of
lower unsaturated alcohols.
[0064] Comb-like polymers are polymers in which carbon radicals
having at least 8, in particular at least 10, carbon atoms are
bonded to a polymer skeleton. They are preferably homopolymers
whose alkyl side chains contain at least 8 and in particular at
least 10 carbon atoms. In the case of copolymers, at least 20%,
preferably at least 30%, of the monomers have side chains (cf.
Comb-like Polymers--Structure and Properties; N. A. Plat and V. P.
Shibaev, J. Polym. Sci. Macromolecular Revs. 1974, 8, 117 et seq.).
Examples of suitable comb-like polymers are fumarate/vinyl acetate
copolymers (cf. EP-A- 0 153 176), copolymers of a
C.sub.6-C.sub.24-.alpha.-olefin and an N-C.sub.6- to
C.sub.22-alkylmaleimide (cf. EP-A-0 320 766) and furthermore
esterified olefin/maleic anhydride copolymers, polymers and
copolymers of .alpha.-olefins and esterified copolymers of styrene
and maleic anhydride.
[0065] The novel fuel oils of the present invention may comprise
other additives, for example, dewaxing assistants, corrosion
inhibitors, antioxidants, lubricity additives and sludge
inhibitors.
EXAMPLES
[0066] The following additives A1 to A5 were prepared:
[0067] A1: Ethylene-MA copolymer imidated with coconut fatty
alkylamine and comprising 30% by weight (8 mol %) of MA.
[0068] A2: Ethylene-VeoVa copolymer comprising 7 mol % of VeoVa 10
and having a V.sub.140 of 200 mPas.
[0069] A3: Ethylene-VeoVa copolymer comprising 14 mol % of VeoVa 10
and having a V.sub.140 of 270 mPas.
[0070] A4: Ethylene-VeoVa copolymer comprising 7 mol % of VeoVa 11
and having a V.sub.140 of 84 mPas.
[0071] A5: Copolymer of ethylene and 8 mol % of stearyl acrylate,
having a V.sub.140 of 65 mPas.
[0072] MA=maleic anhydride
[0073] VeoVa 10/11=vinyl neodecanoate/neoundecanoate
[0074] V.sub.140=melt viscosity of the copolymer, determined
according to ISO 3219 using the plate-and-cone measuring system at
140.degree. C.
[0075] Efficiency of the Additive
[0076] Table 3 shows the efficiency of the additives as flow
improvers for mineral oil distillates on the basis of the CFPP test
(Cold Filter Plugging Test according to EN 116) in different
distillates from Scandinavian refineries. The additives are used as
50% strength solutions in Solvent Naphtha. As a comparison, the
efficiency of a commercial ethylene-vinyl acetate copolymer (EVA
copolymer) containing 13.3 mol % of vinyl acetate and having a melt
viscosity V.sub.140 of 125 mPas (V1) and that of a commercial
ethylene-vinyl acetate-vinyl neodecanoate terpolymer containing 16
mol % of vinyl acetate and 1.2 mol % of vinyl neodecanoate and
having a melt viscosity V.sub.140 of 140 mPas (V2) are shown.
1TABLE 2 Characterization of the test oils: Test oil 1 Test oil 3
Test oil 4 Test oil 5 Test oil 6 Initial boiling 195.degree. C.
127.degree. C. 190.degree. C. 192.degree. C. 183.degree. C. point
20% 226.degree. C. 193.degree. C. 219.degree. C. 218.degree. C.
226.degree. C. 90% 280.degree. C. 318.degree. C. 291.degree. C.
288.degree. C. 330.degree. C. 95% 300.degree. C. 330.degree. C.
311.degree. C. 306.degree. C. 347.degree. C. Cloud Point
-30.degree. C. -23.degree. C. -24.degree. C. -27.degree. C.
-9.degree. C. CFPP -31.degree. C. -23.degree. C. -29.degree. C.
-34.degree. C. -12.degree. C. Pour Point -30.degree. C. -42.degree.
C. -27.degree. C. -27.degree. C. -21.degree. C. CFPP-PP -1.degree.
C. 19.degree. C. -2.degree. C. -7.degree. C. 9.degree. C. Density
(15.degree.) 0.821 0.822 0.817 0.819 0.835
[0077] The CFPP is determined according to EN116 and the PP
according to ISO 3016 using an automatic apparatus (Herzog MC
852).
2TABLE 3 CFPP efficiency Test oil 1 Test oil 3 Test oil 4 Test oil
5 Test oil 6 100 200 400 1000 100 200 400 100 250 500 50 100 250 50
100 200 ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm
ppm A1 -38 -40 <-40 <-40 -36 -36 -40 -39 -39 <-40 A2 -38
-39 -40 <-40 -28 <-40 <-40 -36 -38 -39 -18 -20 -23 A3 -33
-35 -38 -40 <-40 <-40 <-40 -16 -17 -19 A4 -36 -38 -39
<-40 A5 -39 <-40 <-40 <-40 V1 -37 -35 -35 -34 -26 -38
<-40 -35 -34 -34 -39 -36 -35 -17 -20 -22 V2 -33 -35 -35 -33 -26
-35 -39 -35 -34 -33 -11 -15 -22
[0078] List of the Tradenames Used
3 Solvent Naphtha aromatic solvent mixtures having a boiling
SHELLSOL .RTM. AB range from 180 to 210.degree. C. SOLVESSO .RTM.
150 aromatic solvent mixture having a boiling range of from 180 to
210.degree. C. SOLVESSO .RTM. 200 aromatic solvent mixture having a
boiling range from 230 to 287.degree. C. EXXSOL .RTM. dearomatized
solvent having various boiling ranges, for example EXXSOL .RTM.
D60: 187 to 215.degree. C. ISOPAR .RTM. (Exxon) isoparaffinic
solvent mixture having various boiling ranges, for example ISOPAR
.RTM. L: 190 to 210.degree. C. SHELLSOL .RTM. D mainly aliphatic
solvent mixtures having various boiling ranges
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